Lafora's disease (LD, OMIM 254780) is the most common and severe form of adolescent-onset progressive epilepsy. Increasing seizures are paralleled with an insidious cognitive decline towards dementia, and death usually within 10 years of onset (1,2). At the cellular level, LD is characterized by an endoplasmic reticulum (ER)-associated accumulation (3) of starch-like glucose polymers (4) called polyglucosans (or Lafora bodies). Inheritance is autosomal recessive with genetic heterogeneity but the clinical presentation is homogeneous (5). The inventors previously discovered that mutations in the EPM2A gene on chromosome 6q24 encoding a dual-specificity phosphatase (named Laforin) with a carbohydrate binding domain, cause LD (6, 7 and WO 00/05405).
There is a need in the art to identify other genes involved in Lafora's disease to assist in the diagnosis and treatment of Lafora's disease.